Under the Weather: us and the elements, by Tom Fort

Can a downpour lose you a war?

Conversations about the weather may be predictable, repetitive and plain dull, argues Tom Fort, but the weather itself is fascinating. Even a little storm he witnessed in Berkshire, which did nothing more than rain off half an inconsequential cricket match, offered "surprise, excitement, theatrics and beauty to console us for the termination of our fun".

Fort is a skilful descriptive writer and his book includes many sharp vignettes of the weather in particular landscapes on particular days. Interwoven with them is an account of how successive generations have slowly developed the science of meteorology. This features some splendid English eccentrics such as Dr George Merryweather, inventor of the Tempest Prognosticator - a bottle filled with leeches which activated a bell to signal an approaching storm. Progress also depended on the many humbler obsessives who measured local rainfall and air pressure every day for decades, although Fort admits that their amateur weather journals do not make for stimulating reading. (Judging by the quotes, this is a considerable understatement.)

In the cosy world of Berkshire storms and curtailed cricket matches, bad weather is simply an inconvenience. At other times and places, it has often been a matter of life and death - and regarded as divine punishment for sin. Yet it remains difficult to determine how far we are affected by the weather. Does it truly influence our moods and energy levels, or is that just a convenient excuse for our own failings? Has it ever had a decisive impact on the result of a major battle?

These are interesting themes and Fort assembles some entertaining material on them all, and on theories that national character is forged by climate. One German writer believed that the English weather produced "the happy temper, intrepidity and continual activity of the people". A French historian called Emile Boutmy made huge generalisations about the impact of "mist and moisture" on the English imagination without noticing that the climate in Paris, where he taught, was hardly any different. Fort marshals his evidence well but then, unfortunately, often feels compelled to add personal reflections so bland and inconclusive that all energy seeps out of the book.

Meteorology, he suggests, was once a genuinely difficult subject both because of the number of variables and because the key processes took place in "a region inaccessible for observation". It has also attracted many cranks lacking basic common sense. One used extensive statistical data to argue that storms encouraged people to visit libraries because of the "psychologically energising" effect of falling pressure. So when did meteorology become truly scientific and start making predictions more detailed and reliable than traditional rural weather wisdom? Fort cites arguments that Met Office forecasts are not particularly accurate, at least in times of changeable weather, and suggests that they function more as a reassuring national ritual than a source of genuine information.

Yet crucial issues are at stake here. If climatology is now a proper science, we all ought to be getting pretty worried about global warming. The final chapter of Under the Weather pokes fun at the shrill doom-merchants, and the way some of the media portrayed the lovely summer of 2003 in apocalyptic terms. But when it comes to assessing the risks, it suddenly goes soft and offers nothing better than a long list of hypotheticals: "It could be that global temperatures will not rise by as much as the majority of climatologists think... that the equation will be suddenly upset by factors that have been entirely overlooked... ". Little over a page later, Fort signs off with a return to his rural idyll: "Outside, the breeze is tugging at the branches of the cherry tree that stands guard over our garden." Many of us avoid thinking about global warming, but this is quite astonishingly evasive. As so often in England, talking about the weather turns out to be a great way of not talking about other, more important things.